The present invention relates to a path setting method and apparatus for setting channels via which to transmit audio signals from desired signal supply sources to desired signal supply destinations in an audio system which comprises a plurality of devices and an audio network interconnecting the plurality of devices.
The present invention also relates to an audio system which comprises a control device, a plurality of devices and an audio network interconnecting the plurality of devices, and more particularly to a technique for setting connections between the devices.
The present invention also relates to an audio system which comprises a control device, a plurality of devices and an audio network interconnecting the plurality of devices, and more particularly to allocation of transmission channels provided in the network.
One of the mixing systems, which has been marketed by the assignee of the present application under the product name “PM1D”, is a system implemented by separate hardware devices for performing a function of a mixing console (control device) operable by a human operator to make a desired input using various controls, a function of a signal processing section (mixing engine) for performing audio signal processing corresponding to human operator's input to the mixing console and a function of an input/output device (I/O device) for inputting and outputting audio signals. In this system, the mixing engine and the I/O device and the console are interconnected via digital-audio-signal communicating audio cables so that a plurality of digital audio signals can be communicated (transmitted and received) between the engine and the various devices. Further, the console and the engine are interconnected via a control cable for communicating control signals so that the engine can be remote-controlled by the console via the control cable.
The I/O device includes a plurality of input terminals (input ports) and a plurality of output terminals (output ports). An audio signal is input to each of the input ports, and an audio signal is output per each of the output ports. The mixing engine includes a plurality of input channels to which are connected the individual input ports of the I/O device. An audio signal input via each of the input ports is supplied to the input channel connected with the input port. The mixing engine includes a plurality of output channels to which are connected corresponding output ports of the I/O devices. An audio signal output from each of the output channels is supplied to the output port connected with the output channel. Throughout this specification, allocating one input channel as a connection destination of one signal supply source, i.e. allocating one signal supply destination as a connection destination of one signal supply source will hereinafter be referred to as “patch”.
In the conventionally-known mixing systems, setting of input patches for allocating input channels to input ports of an I/O device and setting of output patches for allocating output channels to output ports is performed by an input patch function and output patch function, respectively, provided by a mixing console. More specifically, an operating screen equipped with the input patch function and output patch function is displayed on a display device of the console. A human operator is allowed to instruct connecting a desired input channel to a desired input port and connecting a desired output channel to a desired output port through simple operation on the operating screen, as disclosed in “PM1D Version—2brochure (pamphlet)”, [online], made November, 2005 by Yamaha Corporation, Internet <URL:http://proaudio.yamaha.co.jp/downloads/brochures/mixers/pm1dv2_brochure/ja.pdf> (hereinafter referred to as non patent literature 1.
Further, audio network systems have heretofore been known, in which audio signals are transmitted between a plurality of nodes. In such audio network systems, the nodes are interconnected via network cables of the Ethernet (registered trademark) standard. The “nodes” are individual devices constituting the network. Japanese Patent Application Laid-open Publication NO. 2008-99264 (hereinafter referred to as “patent literature 1”, for example, discloses an audio network where audio signals are transmitted among a plurality of nodes, connected to the network, by a “sound transmission frame” making a round through all of the nodes. The audio network thus arranged allows audio signals of hundreds of channels to be transmitted, in a substantially real-time manner, between all of the plurality of nodes, using a plurality of transmission channels provided in the sound transmission frame. Further, with the sound transmission frame, control data etc. of the Ethernet can be transmitted simultaneously with the audio signals, as disclosed in for example in patent literature 1.
In a case where the audio network disclosed in patent literature 1 is applied to a mixing system, i.e. where the I/O device, the engine and the console are interconnected via the audio network cables, the audio network intervenes among these devices. Thus, settings of input and output patches between two of the devices connected via the network must be made together with settings of the sound transmission frame (i.e., allocation of transmission channels), which would inconveniently involve cumbersome operations. In order to set a patch between an input port of the I/O device and an input channel of the engine, for example, it is necessary to make a setting for supplying a signal of the input port of the I/O device to a transmission channel and a setting for causing the engine to receive the signal of the transmission channel and allocating the input channel of the engine to the received signal, in addition to allocating the input channel to the input port.
Namely, in the case where the audio network disclosed in patent literature 1 is applied to the mixing system, the conventional input patch function and the conventional output patch function alone are not sufficient. Thus, it is presently desired to set, in a straightforward and simplified manner, a patch between an input port and an input channel of the two devices interconnected via the audio network and a patch between an output port and an output channel of the two devices.
Further, for audio signal routing (transmission channel setting) using a network, it is common to employ a routing scheme which sets a connection from a supply source of an audio signal to a supply destination of the audio signal and then reserves a transmission band (transmission channel) to be used for transmission of the audio signal through the connection. In such a routing scheme, negotiation is performed between the supply source and the supply destination after the supply source and destination confirming each other's presence on the network, so that a connection is set between the supply source and the supply destination and one transmission band (transmission channel) is allocated to the thus-set connection. Then, the connection is implemented by an audio signal being transmitted between the supply source and the supply destination using the allocated transmission band.
The aforementioned routing scheme, however, presents the inconvenience that it would take a long time until the connection is actually implemented after a human operator (user of the system in question) performs operation for setting the connection. Further, because the allocation of the transmission bands is made to the connections between the supply sources and the supply destinations, the aforementioned routing scheme also presents the inconvenience that complicated mechanisms would be required if the human operator wants to limit the transmission bands to be used by the device possessing the supply sources and by the device possessing the supply destinations.
Furthermore, in a mixing system where a mixing engine functions as a center of audio signal transmission paths of the system as in the mixing system disclosed in non-patent literature 1, all transmission paths of audio signals are set via the mixing engine. Thus, when the power supply to the engine has been turned off or the engine is disconnected, there would arise the inconvenience that signal processing, including transmission of audio signals, can no longer be performed in the system as a whole. Therefore, there is a demand for a mixing system in which, even when any one of devices in the system, including a device functioning as a center of audio signal transmission such as an engine, has been disconnected, can continue transmission of audio signals between the remaining devices.
Further, in the mixing system disclosed in non-patent literature 1, routing (i.e., transmission path setting) of audio signals is performed by a control device (console or personal computer) that controls the entire system. Namely, a human operator makes, via the control device, a patch setting for connecting a desired supply source and a desired supply destination, and transmission paths of audio signals are controlled in accordance with the patch setting. In such a construction, there would arise the inconvenience that the transmission paths of audio signals can no longer be controlled when the control device has been disconnected from the mixing system in operation. Thus, there is a demand for a mixing system which, even when the control device (e.g., console) for controlling the entire system has been disconnected, can continue controlling the transmission paths of audio signals.
Furthermore, if the mixing system is constructed in such a manner that the transmission paths of audio signals can be controlled even with no control device being present in the mixing system, and when a control device has been newly connected to the mixing system in operation, there is a possibility of discrepancy occurring between transmission paths of audio signals set previously with no control device present in the mixing system and transmission paths set with the newly connected control device. Such discrepancy can be eliminated by synchronizing between data of the control device and data of the individual other devices (i.e., overwriting the data of one of the control device and other devices with the data of the other). At that time, it is desirable that synchronizing directions for connections to particular supply sources and connections between particular devices can be controlled in accordance with a user's (or human operator's) desire.
Furthermore, if the transmission bands (transmission channels) have run short, part of the connections set by the human operator can no longer work. In such a case, it is difficult for the conventionally-known technique to allow, through simple control, a human operator's desire to be reflected in which of the connected connections should be caused to work preferentially.
Furthermore, when the transmission bands (transmission channels) have run short and any of the transmission channels currently in use has to be released, it is difficult for the conventionally-known technique to allow a human operator's desire to be reflected in which of the transmission channels currently in use for connections should be released.
It is desirable that each transmission path to be reserved as a permanent audio signal transmission path should not be made an object of the release or should be less likely to be made an object of the release.